hi, please, how to decide the boundary condions for a free turbulent jet in a case of wall in slip without friction and the forme used of the inlet velocity. sincerly.

(1). Schlichting's book, "Boundary Layer Theory" has a chapter on free turbulent flows, including the close form solutions of 2-D jet and round jet. (beware of the typing errors in the old edition.) (2). If you pack the mesh around and in the jet, also with large enough computational domain, you should be able to get good solutions regardless of the exact boundary conditions used.